This study proposes to study chemical in vitro carcinogenesis of the bovine pancreatic duct and to correlate the premalignant and malignant alterations observed with those seen in the human pancreas by the following: (1) To characterize in detail the normal morphology of bovine pancreatic ductal epithelium and compare it with changes seen in premalignant and malignant states using high resolution light microscopy and electron microscopy. Selected cytochemical techniques will be employed at the light and electron microscopic level. (2) To study the metabolic and morphologic response of the cultured bovine pancreatic ductal epithelium to carcinogens such as 7, 12-dimethylbenz(a)anthracene (DMBA) and N-nitrosoguanidine. (3) To compare this animal model with on-going studies in the human pancreatic duct.